Peter of Spain

Peter of Spain (thirteenth century), exact identity unknown, was the
author of a standard textbook on logic, the Tractatus
(Tracts),[1]
which enjoyed a high renown in Europe for many centuries. His works
on logic are typical examples of the type of manuals that gradually
started to emerge within the context of twelfth- and
thirteenth-century teaching practices. Until recently he was also
identified as the author of a number of extant works on medicine.

Peter of Spain has been established as the medieval author of a work
that became widely known as Summule logicales magistri Petri
Hispani (Collection of Logic Matters of Master Peter of Spain).
The great number of manuscripts and printed editions is evidence of
the enormous success this work met with throughout European
universities well into the seventeenth century. An interpolated
version of his Tractatus, by then known as the Summulae
logicales, was used by John Buridan as a basic text to comment
upon. But finding out the true identity of the author of this
influential Tractatus has proved to be a difficult task. For
a long time it was assumed that he was a Portuguese who became Pope in
1276, under the name of John XXI. There is also another, earlier
tradition, according to which the author of the Tractatus was
regarded as Spanish, and a member of the Dominican order. Yet another
attribution, dating from the fifteenth century, was to a Petrus
Ferrandi Hispanus (d. between 1254 and 1259), which would be
consistent with the idea that the work originated from the first half
of the thirteenth century. According to still another attribution, the
Summule was compiled by a Black Friar no earlier than in the
late thirteenth or early fourteenth century.

The ‘Dominican-thesis’ can be divided into three
traditions:

The general view that Peter of Spain, author of the
Tractatus, is someone who belonged to Order of Black
Friars,

The more specific view that the author of the Tractatus
was a frater Petrus Alfonsi Hispanus O.P.,

Another specific view that the Peter of Spain who created the
Tractatus was the same Peter of Spain as the one who wrote the
Legenda sancti Dominici and the Office of the Saint's Feast,
namely Petrus Ferrandi Hispanus O.P., who died in the 1250's.

Current research on the identity of Peter of Spain has once again taken
up the idea that he must have been a member of the Dominican Order
instead of Pope John
XXI.[2]
However, we are still in the dark about the true identity of Peter of
Spain. The most recent information we have on this score is that a
number of the Dominican candidates recently suggested as the author of
the Tractatus can be deleted from the
list.[3]
The lack of further information also makes it difficult to establish
the dates and specifics of his carreer.

The work that has enjoyed such enormous success, the
Tractatus, is believed to have been written between 1230 and
1245 and has universally been recognised as a work by Peter of Spain.
Another work that has been identified as Peter of Spain's is a
Syncategoreumata (Treatise on Syncategorematic Words),
probably written sometime between 1235 and
1245.[4]
Considering the fact that in all the thirteenth-century manuscripts
the Syncategoreumata directly follow the Tractatus,
and the number of similarities between doctrinal aspects of these two
works on logic, it is almost certain that they were written by the
same author. Both works seem to have originated from Southern France
or Northern Spain, the region where we also find the earliest
commentaries on these treatises.

Besides these works on logic, there are other works that have been
written by a Peter of Spain. In the Petrus Hispanus papa
tradition, he is the supposed author of a famous medical work
Thesaurus pauperum, as well as fourteen other works on
medicine. Other works written by (a) Peter of Spain are a Scientia
libri de anima, and commentaries on Aristotle's De
anima, De morte et vita and De sensu et
sensato, and commentaries on works by pseudo-Denys the
Areopagite. As yet there is no certainty about whether the Peter of
Spain who wrote these works is the author of the Tractatus
and the Syncategoreumata, or about the dates of their
origin.

Another Peter of Spain, referred to as Petrus Hispanus
non-papa, has been identified as the author of the Summa
‘Absoluta cuiuslibet’, a late twelfth-century
handbook on syntax closely linked with Priscian's Institutiones
grammatice, libb. XVII and XVIII, which became very popular later
in the Middle Ages under the name Priscianus
minor.[5]
The chronology of this work seems to rule out that this Peter of
Spain is the same author as the author of the Tractatus.

Peter's logic has its origin in the continental tradition. The
educational carreer of the Tractatus appears from two
commentaries,[6]
which contain short lemmata and a number of questions
(questiones) together with their solutions. The tracts as
contained in these texts are very similar to the ones in the
Tractatus. Typical of the Paris tradition is the separate
treatment of ampliation, restriction and distribution, and several
other, doctrinal
features.[7]
Peter's Masters include Johannes Pagus (who is supposed to have been
a Master of Arts in Paris in the 1220's) and Hervaeus Brito (who may
have been a Master of Arts either before 1229, but possibly later, in
which case he does not qualify as a teacher of Peter's). Besides these
direct influences, the sources for Peter's works on logic can be
traced back to Boethian-Aristotelian logic, and authorities in the
field of grammar such as Priscian and Donatus.

Like the Tractatus, the Syncategoreumata also
displays a continental origin, and appears to have continued along the
lines of a similar work by Johannes Pagus (which has been dated
between 1225 and 1235), later on further developed by Nicholas of
Paris (who wrote his Syncategoreumata between 1240 and
1250).[8]

The Tractatus can be divided into two main parts. One part
deals with doctrines found in the so-called
logica antiquorum—i.e., the logica vetus (old logic) and logica nova
(new logic)—and the other contains doctrines covered by the
logica modernorum—viz. the tracts that discuss the
proprietates terminorum (properties of terms).

The first main part of the Tractatus divides into five
tracts. The first tract, De introductionibus (On introductory
topics) explains the concepts used in traditional
logic—nomen (noun), verbum (verb), oratio
(phrase), propositio (proposition)—and presents the
divisions of and the (logical) relationships between propositions. The
second tract, De predicabilibus (On the predicables) covers
matters dealt with in Boethius's accounts of Porphyry's
Isagoge. It gives an account of the concept
predicabile and the five predicables—genus,
species, differentia, proprium,
accidens—i.e., the common features of and differences
between the predicables, as well as of the terms
’predicatio’ and
’denominativum’. Tract three, De
predicamentis (On the categories), discusses the ten Aristotelian
categories, as well as some items already dealt with in the previous
treatise. The fourth tract, De sillogismis (On syllogisms)
mainly goes back to Boethius's De syllogismis categoricis (On
categorical syllogisms). It gives an explanation of the basic element
of the syllogism, i.e., propositio, and of the syllogism, and
then goes into mood and figure, the proper forms of syllogisms, and
briefly deals with what are called paralogisms. The fifth tract,
De locis (On topical relationships), is derived from
Boethius's De topicis differentiis (On different topical
relationships) I and II. This tract starts off with an explanation of
the notions argumentum and argumentatio, and then
proceeds to deal with the species of argumentation: syllogism,
induction, enthymeme, and example. Next, it gives a definition of
locus (the Latin translation of the Greek topos): a
locus is the seat of an argument (i.e., the locus is
supposed to warrant the inference by bringing it under some generic
rule.) The intrinsic loci (= the kind of locus that
occurs when the argument is derived from the substance of the thing
involved) are covered first, followed by the extrinsic loci
(= the kind of locus that occurs when the argument is derived
from something that is completely separate from the substance of the
thing involved) and intermediary loci (= the kind of
locus that occurs when the argument is taken from the things
that partly share in the terms of the problem and partly differ from
it). Examples are: intrinsic—the locus "from definition":
‘a rational animal is running; therefore a man is
running’; extrinsic—the locus "from opposites":
‘Socrates is black; therefore he is not white’;
intermediary—‘the just is good; therefore justice is
good’.

The second part of the Tractatus comprises subjects that
were of major importance in the doctrine of the properties of terms. In
the sixth tract, De suppositionibus, the theory of supposition
is dealt with. The treatise begins with an exposition of
significatio. The definition of significatio runs:
significatio is the respresentation of a thing by means of a
word in accordance with convention. Next it gives a definition of the
related terms suppositio and copulatio, and the
differences between the terms significatio,
suppositio and copulatio. Of these three
suppositio and significatio are the most important in
Peter's semantics. Suppositio is defined as the acceptance of
a substantive verb for some thing. Suppositio is dependent on
significatio, because supposition can only occur via a term
that already has some significatio. Put in other words,
significatio pertains to a word by itself, and
supposition to a term as actually used in some context.

The tract concludes with a division of suppositio. The
first division is into suppositio communis (common
supposition) and suppositio discreta (discrete
supposition)—e.g., the terms homo (man) and Sortes (Socrates)
respectively.

The second division, suppositio communis, is divided into
naturalis (natural) and accidentalis (coincidental).
Suppositio naturalis is described as the acceptance of a
common term for all those things that can share in the common universal
nature signified by the term in question—e.g., homo
(‘man’) taken by itself by its very nature is able to stand
for all men, whether in the past, present or future; suppositio
accidentalis is the acceptance of a common term for those things
for which the term in question requires an additional term—e.g., in
homo est (‘A man is’) the term homo
stands for present men, whereas in homo fuit (‘A man has
been’) and in homo erit (‘A man will be’) it
stands for past men and future men respectively, owing to the
additional terms fuit and erit.

The third division, suppositio accidentalis, is divided
into suppositio simplex (simple supposition) and
suppositio personalis (personal supposition). Suppositio
simplex is the acceptance of a term for the universal
‘thing’ it signifies, as in homo est species
(‘Man is a species’, animal est genus
(‘Animal is a genus’), in which the substantive terms
homo and animal stand for the universal man and
animal, and not any one of their particulars. Suppositio
simplex can occur both in the subject- and in the
predicate-term—e.g., homo est species (‘Man is a species’) and
omnis homo est animal (‘Every man is an animal’)
respectively. Suppositio personalis is the acceptance of a
common term for one or more of its particulars, as in homo
currit (‘A man is running’).

The fourth division, suppositio personalis, is subdivided
into either derterminata (determinate = standing for a certain
particular) or confusa (confused = standing for any individual
falling under that name). Suppositio determinata occurs when a
common term is taken indefinitely or in combination with a particular
sign—e.g., homo currit (‘Man is running’) or
aliquis homo currit (‘A /some man is running’).
Suppositio confusa occurs when a common term is taken in
combination with a universal sign (’Every man is
running’).

The tract on supposition winds up with the discussion of a few
questions regarding the attribution of supposition in a few cases.

The seventh tract of the Tractatus, on fallacies, which forms
part of the Aristotelian-Boethian logic, is written in the tradition
of the Fallacie maiores (Major fallacies). The eighth tract,
De relativis (On relatives) deals with the relative pronouns
as defined by Priscian in his Institutiones grammaticae. The
relative pronouns are devided into: relatives of substance, such as
qui (who), ille (he), alius (another), and
relatives of accident, such as talis (of such a kind),
qualis (of what kind), tantus (so much),
quantus (how much). The former are subdivided into relatives
of identity (qui and ille) and relatives of
diversity (such as alter and reliquus, both of which
can be translated as ‘the other’). The relative of
identity is defined in terms of supposition as what refers to and
stands for the same thing. These relatives are either reciprocal or
non-reciprocal. With regard to the relatives of identity, Peter adds a
dicussion of a number of questions about the rationale for using
demonstrative pronouns, and some problems concerning how the fallacy
of a relative having two diverse referents comes about.

The tract on relatives continues with a brief discussion on the
relatives of diversity, accompanied by a rule about the supposition of
the relative when it is added to a superior and an inferior in a
premiss and a conclusion, as in aliud ab animali; ergo
aliud ab homine (‘Something other than an animal; therefore
something other than a man’). With regard to relatives of
identity a rule of the "ancients", who deny that a proposition
introduced by a relative can have a contradictory opposite, is
discussed and rejected. Another rule is given about the identity of
supposition of a non-reciprocal relative and what it refers to. The
tract concludes with short accounts of relatives of accident.

The ninth, tenth, eleventh, and twelfth tracts of the
Tractatus, i.e., the short tracts De ampliationibus
(On ampliation), De appellationibus (On appellation), De
restrictionibus (On restriction) and De distributionibus
(On distribution) are in fact elaborations of the theory of
supposition. Ampliation is an extension of the supposition of a term.
It occurs when an expression is combined with a modal term—e.g.
homo potest esse Antichristus (‘A man can be the
Antichrist’), and homo necessario est animal (‘A
man is necessarily an animal’)—in which case the supposition
of the term ‘man’ is extended to more than just
individuals existing in the present. The tract on
appellationes is very short: appellation is considered no
more than a special case of restriction, i.e., the restricted
supposition brought about by a present-tense verb. In this tract the
rules of appellation are in fact specific kinds of rules of
restriction. The subject of restriction in general is discussed in the
eleventh tract. The rules of restriction are the same ones as were
presented in the early Parisian textbooks on
logic.[9]
The final tract, on distribution, deals with the multiplication of
common terms as a result of their being combined with universal
signs. These universal signs are either distributive of substance
(such as omnis, nullus), or of accidents (such as
qualiscumque, quantuscumque). In this description
‘substance’ is defined as substistent modes of being, and
‘accident’ as accidental modes of being. Separate
attention is given to the universal sign omnis
(‘all’ or ‘every’) along with a discussion of
the common rule that the use of omnis requires three
appellata (particular things). The most frequently cited
example in these discussions in the thirteenth century was the
sophisma omnis phenix est (‘Every phoenix
is’). According to Peter of Spain, the use of omnis
does not call for at least three appellata; an exception to
this rule is found in cases in which there is only one
appellatum, as is the phoenix-case. The tract also pays
attention to a number of tongue-twisting sophisma-sentences.

Peter's treatise on syncategorematic words forms part of a separate
genre that developed from the beginning of the thirteenth century. The
term syncategorema comes from a famous passage of Priscian in
his Institutiones grammatice II , 15, in which a distinction
is made between two types of wordclasses (partes orationis)
distinguished by logicians, viz. nouns and verbs on the one hand, and
syncategoremata, or consignificantia, on the other.
The latter are defined as words that do not have a definitive meaning
on their own, but acquire one only in combination with other,
categorematic words.

Like the treatises of the Tractatus kind, the
Syncategoreumata were developed from the (twelfth-century)
theories on fallacies, as well as from grammatical doctrines (from the
same period). From the second half of the twelfth century, there was a
growing interest in the linguistic elements that are considered to lie
at the basis of ambiguity and fallacious reasoning. Hence the increase
of treatises presenting a systematic account of these terms. The
connection these treatises have with Priscian's grammar can be
gathered from the attention different authors pay to the signa
quantitatis (or quantifiers), and the fact that considerable
attention is given to the meaning and function of syncategorematic
terms.

The list of words to be included among the syncategoreumata
was not always the same. Generally speaking it comprised exclusive
words tantum (only), solus (alone), exceptive words
such as preter (except), nisi (unless), consecutive
words such as si (if) and nisi (if not), the words
incipit (begins) and desinit (ceases), the modal
terms necessario (necessarily) and contingenter
(contingently), the conjunctives an (or), et (and),
nisi (unless), in eo quod (in that), and
quin (that not). In Peter's work we also find a discussion of
the terms quanto (‘how much’ or ‘as much
as’) quam (‘than’ or ‘as’) and
quicquid (whatever). Unlike some other authors (such as
William of Sherwood and Robert Bacon), his list does not include the
word omnis.

In the opening of his Syncategoreumata, Peter presents his
rationale for this investigation, viz. that there is a close link
between the use of these kinds of words in sentences and their
truth-value. His idea is that the syncategoreumata must have some sort
of signification, but not the same as the categorematic words. For this
special kind of signification he uses the words
consignificatio and dispositio.

The first two separate chapters of the Syncategoreumata are
devoted to the words est and non, which are said to
be implied in all other syncategorematic words. Peter's account of the
first word focuses on the notion of compositio (composition),
which is explained in great detail, by looking into the signification
of nouns and verbs (signifying a composition of a quality with a
substance, and that of an act with a substance respectively).
Considerable attention is given to the composition featuring in the
verb ‘is’, in the form of the question of whether the
composition involved can be counted among beings or not, considering
the fact that it can be used to express different kinds of states of
affairs. The chapter on negation introduces the important distinction
between an act as conceived of or in the manner of a concept (ut
concepta sive per modum conceptus) and as carried out (ut
exercita).[10]
Among the former type we find the noun ‘negation’ and the
verb ‘to deny’, whereas the latter is what is meant by the
negative particle ‘not’. The remainder of the chapter
deals with the function of the negation, which is to remove the
composition found in whatever it covers, and discusses some well-known
sophisma-sentences which turn on the specific function of
negation.

The third chapter of the Syncategoreumata discusses the
exclusive words solus and tantum. They are called
exclusives because they carry out an exclusion, not because they
signify one. An exclusion, furthermore, requires four things, namely,
what is excluded, what is excluded from, the respect in which it is
excluded, and the act of exclusion. The kinds of exclusion are divided
into general and specific: the former involves an exclusion from
something generic, whereas the latter from something specific.
Questions that come up in this section have to do with the results of
adding an exclusive term to different kinds of words, such as to a term
falling under the category of Substance: does it exclude only other
substances, or does it also exclude from things listed under another
category? And what if it is added to a term listed under the category
of Accident (such as colour, quantity, and so on)? The next question
deals with the sorts of terms that can be meaningfully associated with
an exclusion. For example, is it possible to exclude something from
‘being’ (as in ‘Only being is, therefore nothing
other than being is’)? The tract proceeds with the kinds of
things that can qualify for an exclusion. The fourth chapter, which
deals with exceptive words, is compiled in a similar manner.

The fifth chapter is about the word si, which is said to
signify causality in or via antecedence. The chapter also contains
discussions of the kinds of consecution or consequence, problems of
inference connected with the referents of terms used in consecutive
sentences, and also on how to contradict a conditional sentence.
Special attention is given to the problem whether from the impossible
anything follows.

The chapter on ‘begins’ and ‘ceases’ is a
good example of the way in which extra-logical considerations found
their way into medieval treatises on logic. Thus, apart from the
semantics and inferential problems connected with the use of these
words in propositions, the chapter also looks into the notions of
motion and time. An important part of Peter's ontological views can be
gathered from chapter seven, which covers issues connected with the use
of modal terms. Chapter eight discusses the signification and use of
connectives, and the final chapter on syncategorematic words proper is
concerned with the expressions quanto, quam and
quicquid. A very short concluding chapter of Peter's
Syncategoreumata deals with a somewhat isolated topic, i.e.
the proper modes of response in an argument. The topics looked into are
solution, the quantity and quality of syllogisms, and the ways to go
about proving a syllogism.

One of the most important elements in Peter's logic concerns the
doctrine of supposition. The theory of supposition has its origins in
the twelfth century, when the medievals showed a growing interest in
the ways in which words function in different contexts. This way of
dealing with the semantics of terms has been dubbed the "contextual
approach".[11]

The primary semantic property of a word is its
significatio, in Peter's definition, the "representation of a
thing by a word in accordance with convention". It is a natural
property of a word, the presentation of some (universal) content to the
mind. The significatio of a word depends on its imposition,
i.e., the application originally given to the word in question. A word
can have more than one significatio, if it was originally
applied to two or more distinct (universal) natures.

The counterpart of significatio, the formal constituent of
every meaning, is the word's capacity to "stand for" different things
(even though its significatio remains the same), depending on
the context in which it is used. In the early stages of the
development of the theory on the properties of terms, this feature of
a word was called appellatio. For instance, the words
‘man’ and ‘horse’ can be used to stand for
different individual men or horses. But they can also stand for
themselves, e.g., when they are used in sentences such as ‘man is
a noun’, or ‘horse is a noun’. Moreover, their
meaning can differ according as the words are used in combination with
verbs of different tenses.

In the final stages of the development of the theory, the notion of
supposition becomes the general label that covers all the uses of a
noun (substantive or adjectival), to which other recognised properties
of terms (appellatio, ampliatio and
restrictio) are subordinated.

The theory of properties of terms shows a radical inconsistency, which
has been explained as "the persistent hesitation of medieval logicians
between the domains of connotation (universals) and denotation
(individuals)."[12]
This inconsistency runs throughout Peter's account of supposition,
and comes to the fore most prominently in what he says about natural
supposition (suppositio naturalis). The main problem is in
what way the property of natural supposition is related to the term's
significatio, which was defined as the acceptance of a word
for a thing (res). By this definition, Peter's concept of
significatio covers both the intension and extension of a
term, the universal nature of man and the individuals that have this
nature in common. Suppositio naturalis, on the other hand, is
described as "the acceptance of a common term for all those things
that can share in a common universal nature"; for example, the term
‘man’ when taken by itself by its very nature stands for
all the individuals that fall under it, whether they exist in the
past, present or future. From this definition and the example just
presented it appears that the extensional features of
significatio and suppositio naturalis overlap. The
latter has been explained by interpreters as the natural capacity of a
significative word to stand for something.

There is a more telling difference between significatio and
suppositio naturalis, however. Significatio is the
natural property of any significative term to represent things, owing
to its original imposition, whereas a term's supposition only enters
the scene when it is used. The expression "taken by itself" (per
se sumptus) found in Peter's account of suppositio
naturalis, does not mean that no context is required, as is the
case in significatio, but it merely indicates that for the
moment the actual context is being disregarded. The link between
significatio and suppositio is the following. When
some word has acquired a signification by an impositor (=
someone who bestows a meaning upon a word), then it connotes a
univeral nature or essence, and acquires a natural capacity to stand
for all the actual and possible individuals that share in this common
nature; it owes this capacity to its significatio. If,
however, we disregard for a moment the actual context in which the
term in question is used and look upon the term as taken by itself
(per se sumptus), then its supposition covers its entire
extension. If we take the factual context in which the term is used
into consideration, then its extension becomes limited, owing to the
context. The context, or more precisely, the added significative term,
can be of three kinds: the added significative term can be a predicate
of a proposition in which the term at issue occurs, the added
significative term can be an adjective, or the context can be of a
social
nature.[13]

The distinction between significatio and suppositio
naturalis persisted throughout the thirteenth and fourteenth
centuries. Behind it is the fundamental view that regardless of
whether a word is used in some context or not, it always has a
significatum, i.e., the universal nature or essence it
signifies, which can be separated from what the word comes to mean in
a specific context.

Besides suppositio naturalis, Peter's (and other medievals')
conception of suppositio simplex also seems to hover between
connotation and denotation. In the expression homo est
species the term homo has suppositio simplex,
but this is precisely too what the term homo signifies. So
there scarcely seems reason to separate signification from supposition
on this score. The specific use of suppositio simplex found
in Peter of Spain and other medieval authors, as the representation of
a universal nature, is rejected later on by authors such as William of
Ockham. For the latter, the term homo in the example just
given has suppositio simplex (for Ockham a special case of
suppositio materialis) in that it stands for the mental
concept of
man.[14]

Peter of Spain's logical works are commonly characterised as revealing a moderately ‘realistic’ outlook. To explain the contents of linguistic expressions and the function of logical terms, he is inclined to focus on their relationships to some extra-mental reality. This can be
shown from the way in which he discusses the use of the word
est (is), his account of suppositio simplex, and the
way he analyses the occurrence of the word ‘necessarily’
in propositions. Moreover, his conception of the consecutive
expression ‘if’ clearly shows his tendency to put the
domains of reality and language on a par. (However, not all linguistic expressions are connected with extramental reality. Although ontology always plays a role in his accounts of language, it would appear that Peter is especially interested in the contents of linguistic epressions. In that regard it seems more appropriate to speak of an intensionalist semantics.)

In his Syncategoreumata, Peter analyses the significative
function of the word ‘is’. To a certain extent his findings
are not confined to that term alone, but cover all verbs, in which the
verb ‘is’ is always understood. The most remarkable feature
about his discussion of ‘is’ is his focus on the notion of
composition. What he is particularly interested in is the kinds of
things affirmative propositions featuring that verb can refer to, in
his words, the type of composition involved in such propositions.

The notion of ‘composition’ plays a prominent role in
Peter's semantics. Before embarking on the specifics of the word
‘is’, he first looks into the compositiones
involved in the noun and the verb. When it comes to the composition
involved in the use of ‘is’, the starting-point for his
account is the question whether the expression ‘is’ in a
proposition of the form ‘S is P’ implies the
‘being’ of the composition. Whether it does or not depends
on how we consider the composition. If we are talking about any
composition whatsoever, in his words, the composition in general, the
composition can indiscriminately be connected with beings and
non-beings. This is because we can talk about both things that are and
things that are not by making use of the same affirmative
propositions. Hence anything expressed by a proposition of the form
‘S is P’ expresses a being in a certain sense (ens
quodammodo). The type of composition he is referring to here is
the mental content of some affirmation, which is something that only
has being to a certain degree. However, the composition in general,
that is, the state of affairs involved in such expressions, is
primarily connected with being rather than non-being. It is when we
talk about non-beings, such as chimaeras, that being in a certain
sense once again enters the scene. Hence a distinction of the types of
being referred to, or the types of composition involved in affirmative
propositions into being in the absolute sense (ens
simpliciter) and being in a certain sense (ens
quodammodo). The difference between these two types of being is
illustrated by the distinction between two types of inference: from
‘A man is an animal’, in which the composition involved is
a being in the absolute sense, it follows ‘Therefore a man
is’, but from ‘A chimaera is a non-being’, in which
the composition is a being in a certain sense only, it does not follow
‘Therefore a chimaera is’.

The counterpart of Peter's discussion of composition is the section
on negation. Peter specifically goes into the question of what it is
the negation denies. In his words, the negation removes the
composition. The composition in this connection is identified with the
affirmed state of affairs (res affirmata). What the negation
removes is not the state of affairs, but the affirmation that goes
along with it. The basis of both composition and negation turns out to
be the same state of affairs, i.e., something that is formulated in the
mind, to which we can either assent or deny to be the case.

The focus on matters of ontology is evidenced in other portions of
Peter's logic as well. For Peter, as for Henry of Ghent (who also
wrote a Syncategoreumata) the expression homo (man)
in homo est animal (‘Man is an animal’) has
simple supposition: it stands for the universal nature of humanity.
Accordingly, the expression is necessarily true, even if no man should
exist. The term ‘necessarily’ thus has ampliative force:
it enables the subject term ‘man’ to refer to individuals
not only existing in the present ( which is the normal case when a
present-tense verb is used), but also to those of the past and the
future. This analysis runs contrary to what is found in some other
Syncategoreumata authors, like Johannes Pagus and Nicholas of
Paris, who maintain that the term ‘necessarily’ does not
have ampliative force. Hence the expression homo necessario est
animal (‘A man is necessarily an animal’) is only
true on the condition that a man exists.

A similar point is made in connection with the use of modal terms.
For Peter of Spain, logical necessity is based upon ontological
necessity, or, the necessity of propositions has its foundation in the
necessity of the things spoken about. Necessity is associated with
different types of things, such as the relationships between certain
concepts (such as genera and species), and the specific things the
notions of which we come across in the different kinds of (scientific)
knowledge (such as mathematical entities and their properties). His
outlook on necessity is clearly revealed in his analysis of the
inference homo necessario est animal; ergo Sortes
necessario est animal (‘A man is necessarily an animal;
therefore Socrates is necessarily an animal’). In his view the
inference is not valid, because a transition is made from necessary
being to a being at a certain time. For Peter then, the notion of
necessity ultimately refers to a necessary state of affairs in
reality, something that is always the
case.[15]

A similar fusion of the domains of language and reality is found in
Peter's account of the consecutive ‘if’, which he explains
as signifying causality. Like his contemporaries he looks into the
question of whether from the impossible anything follows. In his
account, the notion of ‘impossibility’ can be taken in two
ways, viz. impossibility as such, or absolute impossibility, which
amounts to nothing, or the impossible state of affairs that is referred
to when notions of things that do have a reality separately but are
incompatible are combined in statements. From the latter type of
impossibility, such as ‘A man is an ass’, something, but
not anything can follow, e.g., ‘Therefore a man is an
animal’. From impossibilities as such, e.g., ‘You know that
you are a stone’, nothing can follow. The fundamental idea is
that in order to be able to have something follow, the antecedent in
the consecutive relationship must be a something (res) of some
sort.[16]

de Rijk, L.M., 1962–67. Logica Modernorum: A Contribution to
the History of Early Terminist Logic (Vol. I: On the Twelfth
Century Theories of Fallaciesl; Vol. II: The Origin and Early
Development of the Theory of Supposition), Assen: Van Gorcum &
Co.

–––, 1982. “The Origins of the Theory of
the Properties of Terms,” in Norman Kretzmann, Anthony Kenny and
Jan Pinborg (eds.), The Cambridge History of Later Medieval
Philosophy, Cambridge: Cambridge University Press,
pp. 161–173.

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